A trend in recording and playback devices in recent years is the enhancement of various functions for assisting viewing by users. One such function is the creation and playback of digest video of moving picture content. Digest means a reduction of the original playback time of the moving picture content to a relatively short time, and digest video means video reduced to a relatively short amount of time. Using this function enables a two hour-long movie to be viewed in five or ten minutes, for instance.
One example of a method for creating digest video is the following. In a two-dimensional graph, the vertical axis represents the characteristic amount of sound intensity or viewership, and the horizontal axis represents a playback time axis. Threshold values are taken horizontally along the playback axis. Segments where the characteristic amount exceeds the threshold value are judged to be segments for use in the overview video, and the threshold values are modified so that the total time of the segments when concatenated is below a predetermined reference time. The approach taken toward feedback control for modifying the threshold values according to the total time is the crux of conventional digest video creation techniques.